Paging Ebay or Shipping Experts !

I should have thought about this before selling an item on ebay, but the winner is from Russia. The item weighs about 3 - 4 pounds and would be mailed in a medium(?) sized box. I would ideally like insurance and a tracking number but I'm afraid it would be too expensive. Any recommendations? UPS or USPS?

Yeah, it was US bidders the whole time and then, literally at the last second, the guy from Russia bid. He didn't pay yet so maybe I'll do a second chance offer...don't want to get negative feedback though.